You might consider using a figure like what the Internal Revenue Sservice in the US allows us to deduct from our taxes as a transportation expense.
It should be around $0.35 to $0.40 in US dollars now, but I confess, I'm no longer able to use that deduction for business travel so I haven't kept up on it.
If it was $0.35, it would be 2800 x 0.35 = $980 U.S. You would add in any tolls for roadways or bridges, etc.
This method works out fine for vehicle wear and tear and depreciation. Unless you have a major problem on this trip, such as needing 4 new tires, then it would be disappointing.
It's been my general experience that it depends on the number of people that would be in the car as to if it was economical or not. In other words, for two people it might be marginal, for 4 or 5 people, it would be more cost effective to drive..
Hope that helps